1. Field of the Invention
The present invention relates to an apparatus for driving a lens in a camera.
2. Description of the Related Art
Generally, a video camera, a digital still camera, a monitoring camera have an optical apparatus for taking a photograph of an image. Among them, a lens module for performing functions of focusing and/or zooming a target image is installed in a movable manner on a lens barrel. The lens module is reciprocated in the inside of the lens barrel by a predetermined driving force.
For such reciprocating motion, a guide shaft is installed within the lens barrel, and a slider equipped with a zoom lens and/or a focusing lens is installed in a sliding manner on the guide shaft. In addition, a driving motor and a lead screw for reciprocating the slider are installed on the lens barrel. The slider has a power transferring member having a tooth-shaped part for joining to a screw thread of the lead screw on it. The power transferring member is assembled to the slider by a separate part and connected to the lead screw.
However, recently, as light-weight and compact-sizing trends are pursued, the lens barrel, the driving motor and the lead screw are getting smaller in their sizes as well as the lens module. Particularly, as the trend of pursuing accuracy and low power consumption develops for the driving motor and the lead screw, high part accuracy is required. Therefore, if there is an assembling error of the lead screw with respect to the lens barrel, or an assembling error of the power transferring member, connection of the lead screw and the power transferring member may not be smoothly performed. In that case, the tooth-shaped part of the power transferring member may deviate beyond the allowable error range with respect to the axial direction of the lead screw. Accordingly, a big load is applied on the driving motor and big frictional force is applied on the lead screw, so that excessive noise may be generated or normal operation may not be performed.